1. Field of the Invention
The present invention relates to a computer system rack having a rear door heat exchanger and methods of using a rear door heat exchanger.
2. Background of the Related Art
Computer systems use electrical energy and produce heat as a byproduct of electrical resistance. Rack-based computer systems include many rack-mounted components in a high-density arrangement, which can produce a considerable amount of heat. Excess heat must be removed from the rack to control internal temperatures and to maintain system reliability, performance, and longevity. In a conventional rack-based computer system, rack-mounted fans move cool air through the rack to remove the excess heat and cool the components. The heated exhaust air must then be transported to a computer-room air conditioner (“CRAC”) that cools the air before returning the cooled air to the data center.
In a conventional datacenter layout, racks in a data center are commonly arranged in an organized hot-aisle/cold-aisle layout to minimize the likelihood that appreciable volumes of heated exhaust air will directly re-entering the racks. A hot-aisle/cold-aisle layout may include alternating hot aisles and cold aisles, with the front of each rack sharing a cold aisle with one adjacent rack and the rear of each rack sharing a hot aisle with another adjacent rack. The CRAC supplies the cooled air to the cold aisles. The air from the cool aisle is drawn into the front of each rack and the heated air is exhausted through the rear of the rack to the hot aisle. The heated exhaust air recirculates through the CRAC to be cooled and returned back to the cold aisles.
Additional cooling capacity may be added to a data center using a rear door heat exchanger. A rear door heat exchange is typically secured to the back side of a computer system rack and uses a liquid, such as water, as a cooling fluid that is passed through one or more fin tubes. Hot exhaust air from exiting the rack passes over and through the fins so that heat energy is transferred from the air to the liquid. In addition to providing more cooling capacity, the use of a rear door heat exchanger may facilitate data center configurations other than the conventional hot-aisle/cold-aisle configuration.